Circular staircase



May 26, 1970 A. sucKNo CIRCULAR STAIRCASE Filed Oct. 4. 1968 25 I9 e 2O llr/ ssl l? NVENTOR.

ABRAHAM SUCKNO FIG. 2

ATTRNEYS United States Patent Office 3,513,547 Patented May 26, 1970 3,513,547 CIRCULAR STAIRCASE Abraham Suckno, 289 Friar Lane, Mountanside, NJ. 07092 Filed Oct. 4, 1968, Ser. No. 765,'101 Int. Cl. E04f 11/00 U.S. Cl. 52-187 6 Claims ABSTRACT OF THE DISCLOSURE A circular staircase wherein treads are bolted ,to a central column and supported in horizontal channels therein; tread supports in abutment with the central column are bolted thereto; balusters and fascia attached to each other and the treads also reinforce them.

BACKGROUND OF INVENTION This invention relates generally to circular staircases, and particularly to circular staircases made of wood that are designed with great rigidity and strength.

Circular staircases of metal are old and well known. The rigidity of metal makes it ideally suitable for use in a staircase where the peripheral edges of treads are unsupported, or supported only to a limited extent. Circular staircases fabricated of metal members supported on a central metal column are useful in commercial establishments, libraries, and the like, but are out of place in a -private residence. Nevertheless, some residential design requires a circular staircase.

SUMMARY OF THE INVENTION lIt has been found that a circular staircase of wood can be made, which has strength, rigidity, and aesthetic appeal. This is accomplished by providing a central column with horizontal support channels for treads, and at vertical faces for horizontal supports. Balusters and fascias interconnecting the treads to preceding and successive treads provide additional reinforcement, so that the whole structure, with. a rail, provides great rigidity and strength without sacrificing beauty.

DESCRIPTION OF DRAWINGS These objects and advantages as well as other objects and advantages are attained by the device shown by way of illustration in the drawings in which FIG. 1 is a perspective view of the circular staircase;

FIG. 2 is a vertical elevational view of a portion thereof, partially sectioned;

FIG. 3 is a horizontal cross-sectional view taken on the line 3--3 in FIG. 2 looking lin the direction of the arrows; and v FIG. 4 is a horizontal cross-sectional view taken on the line 4-4 in FIG. 2 looking in the direction of the arrows.

DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the drawings in detail, there is provided a base 11 to Vdistribute the weight of the spiral staircase and to support a generally vertical central column l2. The central column 12 may be circular in horizontal cross-section, or may have numerous other cross-sectional configurations, but a dodecahedron is preferred and is shown by way of illustration. A side 13, a suitable distance above the base 11, is provided with a horizontal channel 14 having a vertical wall` 15 parallel to a corresponding -face 16 and perpendicular to the radius of the column 12, so that the top and bottom walls 17, 18 of the channel dene symmetrical seats which have the shape of a truncated isosceles triangle (see dotted lines in FIG. 3). A tread bolt 19 is inserted into the column 12 in the center of the channel 14, equidistant from the ends of the channel 14 and extending radially from the column 12. A generally triangular tread 20 is provided. The tread has a bolt passage 21. The tread bolt 19 may be threaded into a threaded metal socket 22 inserted'in a bore 23. The socket may be cemented in the bore 23. The opposite end of the bolt 19 is passed through the bolt passage 21. A transverse slot 24 permits the application of a nut 25 to the bolt 19 so that the tread 20 is securely mounted in the channel 14. The slot 24 may be capped with a domed plug 26. The broad inner end 27 of the tread 20 is in flat engagement with the vertical wall 15 of the channel 14.

A vertical tread brace 30 is also attached to the column but without a channel. Since a dodecahedral column 12 is provided, the brace 30 has a at inner end 31 in topto-bottom engagement with a portion of a face 13 of the column. A brace bolt 32 is inserted into the column 12, in the middle of a face, and is preferebly threaded into threaded socket 33 cemented into the column 12. The brace bolt 32 is passed through a bore 34 in the brace 30. A transverse slot 35 intersecting with the bore 34 enables the application of a nut 36 to the end of the brace bolt 32. A suitable plug 37 may be used to cap both ends of the slot 35. The brace 30 supports the tread 20 and may extend approximately two-thirds of its radial length.

Each end of the peripheral edge 41 on the tread 20 is notched to receive balusters 40, 40, which are secured thereto in any suitable manner. A succession of treads 20, each offset from its predecessor, are similarly attached in rising ranks around the column 12 in precisely the same manner. A first `baluster 42 has its bottom end resting on the same surface as the base 11. The succeeding -balusters 40, 40 etc. are each attached at the bottom to the inner edge of the peripheral edge 41 on the inferior tread 20, and also to the outer edge of the peripheral edge 41 on the next succeeding superior tread 20. In this manner, the treads 20 are supported at both the inner and outer edges of their peripheral edges 41. The balusters 40 rise sucessively higher and are supports at their upper end for a rail 43. Each baluster 40, etc. has a bottom end 45 that extends lbelow the tread 20 and a fasica 44 extends between the end 45 and the preceding baluster 40, and is attached to the end 45, the preceding baluster, and the bottom of the tread 20. This reinforces the treads 20 at their outer end Iby attaching them to each preceding and succeeding tread and incorporating the support given by each preceding and succeeding brace. In this manner, the strength and rigidity of metal is imparted to a circular staircase of wood. The aesthetic appeal of natural wood and the fluid charm and delicacy of the design impart a quality of grace that renders the wooden circular staircase suitable for residential use, where the rugged functional -design of the metal circular staircase renders it unsuitable.

The foregoing description is merely intended to illustrate an embodiment of the invention. The component parts have been shown and described. They each may have substitutes which may perform a substantially similar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention; these substitutes are contemplated as lbeing within the scope of the appended claims, although they are not specically catalogued herein.

What is claimed:

1. A circular staircase comprising:

(a) a vertical column,

(b) a plurality of llat vertical faces on the column,

(c) a first horizontal channel in the vertical column defining a seat for the inner end of the stair tread,

(d) `a first bolt attached to the column and extending radially from the first channel,

(e) a generally horizontal first stair tread, having a `bolt passage at its inner end, seated in the first channel with the first bolt in the ybolt passage,

(f) a transverse slot in the bottom of the stair tread intersecting with the bolt passage defining a cavity for the application of a nut to the first bolt.

(g) a nut engaged with the first bolt to aflirmatively seat the first tread in the first channel (h) 'a second bolt, below the first bolt, attached to the column and extending radially from a fiat face of the column,

(i) a generally vertical first brace,

(j) a horizontal bolt passage in the first brace,

(k) an inner end on the first brace in fiat abutment with the vertical face from which the second bolt extends and the second bolt in the bolt passage of the vertical brace,

(l) a transverse slot intersecting with the bolt passage of the vertical `brace defining a cavity for the application of a nut to the second bolt,

(m) a nut engaged with the second bolt to affirmatively engage the first brace with the vertical face, (n) the top of the first brace disposed in supporting engagement with the bottom of the first tread, (o) a first baluster attached to the ouer edge of he first stair tread.

2. 'Ihe device according to claim 1, and

(a) a second horizontal channel in the vertical column defining a seat for the inner end of a stair tread,

(b) a generally horizontal second stair tread attached to the vertical column in the second horizontal channel,

(c) a generally vertical second brace attached to the 4 vertical column attached to the second stair tread in supporting relation therewith,

(d) a second baluster attached to the outer edge of the second stair tread, and the inner edge of the first stair tread.

3. The device according to claim 2, and a rail supported by the balusters.

4. The device according to claim l, and a fascia attached to the bottom of the tread and to the first and second balusters.

5. The device according to claim 1, and a vertical wall of the first horizontal channel is disposed horizontally perpendicular to the radius of the column.

6. The device according to claim 1, in which the bottom of the first horizontal channel defines a generally flat, truncated, isosceles triangular seat for the inner edge of the first stair tread.

References Cited UNITED STATES PATENTS 400,470 4/ 1889 Marshall 52-187 839,846 l/1907 Holden 52-187 1,415,739 5/1922 Waggoner 182-228 1,446,454 2/ 1923 Fischer 52-187 1,501,977 7/1924 Weaver 182-217 1,716,713 6/1929 Rossum 52-187 3,233,377 2/1966 Blum 52-191 X FOREIGN PATENTS 106,694 3/ 1943 Sweden. 233,229 4/ 1964 Germany.

FRANK L. ABBOTT, Primary Examiner S. D. BURKE, Assistant Examiner 

